Incidence of Mild Cognitive Impairment with Ascending Altitude
- 1 June 2020
- journal article
- research article
- Published by Mary Ann Liebert Inc in High Altitude Medicine & Biology
- Vol. 21 (2), 184-191
- https://doi.org/10.1089/ham.2019.0111
Abstract
Background: This study aimed to longitudinally quantify the prevalence of mild cognitive impairment (MCI) in individual trekkers at three different ascending altitudes (Site 1: ∼3500 m, Site 2: ∼4400 m, and Site 3: ∼5100 m). We correlated these findings with the presence of acute mountain sickness (AMS). Materials and Methods: We performed serial assays using the environmental quick mild cognitive impairment (eQMCI) score on 103 English-speaking 18- to 65-year-old volunteers trekking to Everest Base Camp in Nepal during spring 2016. We defined MCI as a score less than 67 (lower scores indicating more cognitive impairment). Additional data collected included the Lake Louise Score, demographics, and other possible confounders. Results: eQMCI scores significantly decreased with ascent from Site 1 to 2 (a score of 78.95 [SD = 7.96] to 74.67 [SD = 8.8] [Site 1–2 p = 0.04]), but then increased on ascent to Site 3 to 83.68 (SD = 8.67) (Site 1–3 p = p = N = 7) at Site 1, 18.7% (N = 14) at Site 2, and 3.3% (N = 2) at Site 3. Incidence of AMS at Sites 1, 2, and 3 was 22.3% (N = 23), 21.3% (N = 16), and 48.3% (N = 29), respectively. Of those with MCI, 1.94% met criteria for AMS at Site 1 (p = 0.0017), 2.67% at Site 2 (p = 0.6949), and 3.33% at Site 3 (p = Conclusions: There is a significant incidence of MCI at high altitude, even in those without subjective findings of AMS. Interestingly, subjects with a decline in cognitive function show an increasing trend for developing AMS at higher altitude. Future research on the clinical impact of MCI on a subject's health, judgment, and performance remains to be elucidated.Keywords
This publication has 29 references indexed in Scilit:
- Association of Cognitive Performance with Time at Altitude, Sleep Quality, and Acute Mountain Sickness SymptomsWilderness & Environmental Medicine, 2016
- Cognition at altitude: impairment in executive and memory processes under hypoxic conditions.Aviation, Space, and Environmental Medicine, 2013
- High altitude exposure impairs sleep patterns, mood, and cognitive functionsPsychophysiology, 2012
- Prospective, Double-Blind, Randomized, Placebo-Controlled Comparison of Acetazolamide Versus Ibuprofen for Prophylaxis Against High Altitude Headache: The Headache Evaluation at Altitude Trial (HEAT)Wilderness & Environmental Medicine, 2010
- Cognitive Assessment of a Trekking Expedition to 5100m: A Comparison of Computerized and Written Testing MethodsWilderness & Environmental Medicine, 2009
- The association between neuropsychological scores and ethnicity, language, and acculturation variables in a large patient populationArchives of Clinical Neuropsychology, 2007
- Acute Mountain Sickness: Controversies and AdvancesHigh Altitude Medicine & Biology, 2004
- High-Altitude IllnessThe New England Journal of Medicine, 2001
- The Cost to the Central Nervous System of Climbing to Extremely High AltitudeThe New England Journal of Medicine, 1989
- THE INCIDENCE, IMPORTANCE, AND PROPHYLAXIS OF ACUTE MOUNTAIN SICKNESSThe Lancet, 1976